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This research work was undertaken to evaluate the physicochemical parameters of oil from the cherry kernel non-irradiated and irradiated at 3 and 6 kGy of gamma irradiation for two storage periods (0 and 12 months). The acid value, peroxide value, thiobarbituric acid reactive substances value, iodine value, saponification value refractive index (peroxide value), and the color parameters of cherry kernel oils were determined. The results indicated that the extracted cherry kernel oils were liquid at room temperature with color varying from light yellow to deep red. The physicochemical properties of cherry kernel oils including acid value, peroxide value, thiobarbituric acid reactive substances, iodine value, saponification value, and refractive index values were 1.19 mg KOH g -1 , 9.01 meq 2  kg -1 , 0.014 mg MDA kg -1 , 99.48 KOH g -1 I 2 100 g -1 , 194.50 mg KOH g -1 , and 1.472, respectively. Generally, gamma irradiation doses and storage time increased acid value, peroxide value, thiobarbituric acid reactive substances, and refractive index value of cherry kernel oils, whereas no significant (p > 0.05) change due to irradiation was recorded in iodine value, saponification value, and in color parameter (L*, a*, b*, and ΔE values) of cherry kernel oils. However, the properties of cherry kernel oils revealed that the cherry kernel is a good source of oil which could be used for industrial purposes.

Background: Microbial contamination levels and corresponding sensitivities to gamma rays (GR) and elec- tron beam (EB) irradiation were tested in chamomile (Chamomile recutta L.)., Methods: Chamomile powders were treated with 10 and 20 kGy by GR and EB, respectively. Microbiological and chemical analyses were performed on controls and treated samples immediately after irradiation, and after 12 months of storage., Results: The control samples of chamomile exhibited rather high microbiological contamination, exceeding the levels of 4 log10 CFU g-1   (CFU - colony forming units) reported by national and international authorities as the maximum permissible total count level. Irradiation with GR and EB was found to cause a reduction in microbial contamination proportionate to the dose delivered. The sterilizing effect of EB on microorganisms was higher than the GR one. A dose of 10 kGy of GR and EB significantly (p < 0.05) reduced the total bacte- rial, total coliform and total fungal contamination. A dose of 20 kGy of GR significantly (p < 0.05) reduced the total bacterial and total fungal contamination, while a 20 kGy dose of EB reduced the initial bacterial, total coliform and total fungal contamination to below detection level when the analysis was carried out im- mediately after irradiation treatment or after 12 months of storage., Conclusions: The comparative study demonstrated that electron beam was more effective for decontamination of chamomile powder than gamma irradiation.

The effect on microbial, chemical and sensorial properties of sesame seeds was determined after irradiation and storage. The sesame seeds were analyzed before and after irradiation with 3, 6 and 9 kGy of gamma irradiation, and after 6 and 12 months of storage. The results showed that gamma irradiation had no significant (p>0.05) effect on the moisture, ash and fat content on sesame seeds. While, small differences, but sometimes significant (p<0.05), on protein and sugar contents were recorded between irradiated and non-irradiated samples. Total acidity percentage decreased significantly (p<0.05), while total volatile basic nitrogen (TVBN) increased significantly (p<0.05) due to irradiation. During storage, total acidity increased (p<0.05) and TVBN decreased (p<0.05). Gamma irradiation reduced the microorganisms of sesame seeds. Samples treated with 3 kGy or more remained completely free of fungi throughout the storage. While, only the samples treated with 9 kGy remained completely free of bacteria at the end of storage period (after 12 months). The scores for taste, flavor, color and texture of irradiated samples were higher, but not significantly (p>0.05) than those of non-irradiated samples., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: The aim of the present study was to evaluate the possibility to apply gamma radiation treatment for decontaminating and assuring the quality of peanut seeds., Methods: The radiation processing was carried out at dose levels of 3, 6 and 9 kGy. The irradiated and non-irradiated (control) samples were stored at room temperature for 12 months, and analyzed for microbial load, proximate composition, sensorial acceptance and chemical properties., Results: The results indicated that gamma irradiation treatment significantly (p < 0.05) reduced microbial load and enhanced the safety of the irradiated samples. The irradiated samples were also acceptable sensorically. The total acidity and total volatile nitrogen (TVBN) contents increased with the increase of radiation dose. Furthermore, in general, no substantial change in proximate constituents was observed amongst the samples. No significant (p > 0.05) differences in the taste, flavor, color and texture score were observed among treatments (0, 3, 6 and 9 kGy)., Conclusions: Irradiation protected again bacterial and fungal growth and retained the nutritional components of samples during long-term storage.

The present study evaluated the quality of pistachio oil, as a function of irradiation, to determine the dose level causing undesirable changes to pistachio oil. Physicochemical fatty acid composition, acidity value, peroxide value, iodine value specification number, thiobarbituric acid (TBA) value and colour of pistachio oil extracted from samples treated with 0, 1, 2 and 3 kGy doses of gamma irradiation were determined. Gamma irradiation caused the alteration of fatty acids of pistachio oil which showed a decrease in oleic acid (C18:1) and an increase in linoleic acid (C18:2). All other fatty acids remained unaffected after irradiation. The higher used doses (2 and 3 kGy) decreased acidity value, peroxide value and iodine value, and increased specification number, with no effect on TBA value. Irradiation had a significant effect on colour values of pistachio oil. Parameters L, a and b increased at doses of 1 and 2 kGy., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Purpose: To determine the effect of gamma irradiation, steaming and heating on microbial load and chemical composition of licorice root powder., Materials and Methods: Powders were exposed to hot air treatment at 60°C for 24 h, steaming at 1.1 bar and about 121°C for 15 min, and irradiation at 10 kGy using a (60)Co source. Microbial load, moisture, ash, and electrical conductivity (EC) values of licorice root powders were evaluated immediately after treatment, and after 12 months of storage., Results: Total aerobic plate count (TAPC) of licorice roots powder (control sample), including coliform, Escherichia coli, and Klebsiella spp. were relatively high. Irradiation reduced the TAPC by 4 logs and total coliform to negative (less than 1 log(10) colony forming units (CFU) g(-1)) Klebsiella spp., E. coli, and Salmonella spp. were not detected (less than 1 log(10) CFU/g) in irradiated sample. Meanwhile, heating and steaming reduced the total count by 1 and 2 logs with slight effect on reducing the total coliforms counts. Also, irradiated samples were free of coliforms. No considerable changes in the moisture and ash were observed in irradiated powders, but the moisture increased due to steaming, and decreased due to dried heating., Conclusion: Gamma irradiation at 10 kGy was more effective than heating and steaming treatments in their microbial decontamination effect on the licorice root powders.

Seeds of anise (Pimpinella anisum) were exposed to doses of 0, 5, 10, 15 and 20kGy in a (60)Co package irradiator. Irradiated and unirradiated samples were stored at room temperature. Microbial populations on seeds, total and inorganic soluble solids in water extract and sensory properties of the latter were evaluated after 0, 6 and 12 months of storage. Results indicated that gamma irradiation reduced the aerobic plate counts of aniseed. Immediately after irradiation, the total soluble solids in an extract of irradiated seeds were greater than those of unirradiated ones. The total soluble solids in an extract of irradiated and un-irradiated seeds increased after 6 and 12 months of storage. There were no significant differences (p>0.05) in inorganic soluble solids between the water extract of irradiated and unirradiated aniseeds. Sensory evaluation indicated that gamma irradiation improved sensory characteristics of aniseed water extract tested immediately after irradiation; however, after 12 months of storage, no significant differences (p>0.05) were found in color, taste or flavor between extract of irradiated and unirradiated seeds.

Experiments were carried out to study the effect of different doses of gamma irradiation (0, 5, 10, 15 and 20 kilo gray; kGy) on some nutritive components and chemical aspects pertaining to quality of fish meal and meat-bone meal. The radiation doses required to reduce the total microbial load and Salmonella sp. one log cycle (D(10)) in fish meal and meat-bone meal were determined. Results indicated that gamma irradiation of fish meal and meat-bone meal with 5-20 kGy doses had no effects on the total acidity values but increased the values of lipid oxidation and total volatile basic nitrogen. D(10) of total microbial load and Salmonella sp. were 833 and 313 Gy for fish meal and 526 Gy and 278 Gy for meat-bone meal, respectively. It can be concluded that radiation processing could be employed in the recycling of fish and meat-bone meals by using them as feedstuffs in poultry diets with no fear of losing their nutritive components.

Samples of concentrated municipal sewage sludge, stored for 2, 4 and 6 months, with moisture contents of 2%, 20%, 40%, 60%, and 80% were exposed to doses of 0, 1, 2, 3, 4 and 5 kilogray (kGy) of gamma irradiation. Immediately after irradiation, total microbial count and bacterial pathogens in sewage sludge were determined. The results indicated that in all tested sewage sludge samples, bacterial pathogens including Enterobacter sp., Klebsiella sp., Salmonella sp., and Escherichia coli were initially detected. All doses of gamma irradiation reduced the total counts of microorganisms. D(10) of total count decreased with increase in the moisture content of the sewage sludge. The lowest lethal dose for tested bacterial pathogens was 5 kGy in air dried sewage sludge. In addition for wet sewage sludge having more than 40% moisture, the lethal dose was 1 kGy, for samples taken at different storage periods 2, 4 and 6 months, and therefore the cost per unit could be decreased to half when wet sewage sludge (about 50% moisture) was used.

The aim of this study was to investigate the effect of gamma irradiation on storability of the two main apple varieties, Golden Delicious and Starking, in Syria. The experiments were performed in 1995 and 1996. Fruits were irradiated with 0, 0.5, 1.0 and 1.5 KGy. Irradiated and unirradiated fruits were stored at 1 to 2 degrees C and under a relative humidity of 80 to 90%. Weight loss and spoilage due to physiological disorders and fungal diseases were evaluated throughout the different storage periods. Firmness, coloration and pH values were estimated immediately after irradiation. The results showed that, in both varieties, gamma irradiation increased the weight loss after 45 days of storage in apples gathered in 1995 but not in the 1996 season. After 180 days of storage, gamma irradiation had different effects on weight loss depending on the growing year and variety, and increased fungal spoilage. Application of gamma irradiation prevented the growth of Aspergillus niger and the formation of skin scald in 'Golden Delicious' fruits. Immediately after treatment, gamma irradiation increased the softening of fruits, changed their color from green to yellow and decreased the pH value of the juice.

Eggs and their products such as desserts, confectioneries, bakery mixes, mayonnaise and many convenience foods have been implicated in food-borne disease outbreaks due to microorganism contamination. The effect of gamma irradiation on the presence of microorganisms in egg powder was investigated. Egg powder samples were exposed to several doses of irradiation: 0, 5, 10 and 15 kGy and stored for up to 12 months at ambient temperature (25 ℃). Results indicated that the total viable count (TVC) (5.56 log10 cfu g-1), total coliform counts (TCC) (6.46 log10 cfu g-1) and mold and yeast counts (MYC) (9.12 log10 cfu g) in un-irradiated (control) samples of egg powder were higher than the maximum limits (4.88, 2.00 and 1.70 log10 cfu g-1, respectively). Application of the higher doses (10 and 15 kGy) decreased the TVC, TCC and MYC of the egg powder samples to less than 1 log10 cfu g-1 and the counts remained almost constant during storage for 12 months. D10 values for Escherichia coli and Salmonella typhimurium were 0.714 and 0.278 kGy, respectively. Gamma irradiation treatment could be chosen on the basis of preliminary microbiological tests including TVC, TCC and MYC and help improve the hygienic quality by killing and reducing the microorganisms that might be present inside of egg powder to meet national and international standards. [ABSTRACT FROM AUTHOR]

Abstract: Influence of gamma irradiation and storage on the microbial load, chemical and sensory quality of chicken kabab was investigated. Chicken kabab was treated with 0, 2, 4 or 6kGy doses of gamma irradiation. Treated and untreated samples were kept in a refrigerator (1–4°C). Microbiological, chemical and sensory characteristics of chicken kabab were evaluated at 0–5 months of storage. Gamma irradiation decreased the microbial load and increased the shelf-life of chicken kabab. Irradiation did not influence the major constituents of chicken kabab (moisture, protein and fats). No significant differences (p>0.05) were observed for total acidity between non-irradiated (control) and irradiated chicken kabab. Thiobarbitric acid (TBA) values (expressed as mg malonaldehyde (MDA)/kg chicken kabab) and volatile basic nitrogen (VBN) in chicken kabab were not affected by the irradiation. Sensory evaluation showed no significant differences between irradiated and non-irradiated samples. [Copyright &y& Elsevier]